Stacker



5 Sheets-Sheet 1 vmw a F/zarigs'feaziarz,

RN w July 17, 1928.

1 c. PEARSON STACKER 'F ilqd May 16, 1923 July 17,, 1928.

c. PEARSON STACKER Filed-,May 16, 1923 5 Sheets-Sheet jnvr agz UMZqiPqaigi July 17, 1928.

1,677,488 c. PEARSON STACKER Filed May 16, 1923 '5 Sheets-Sheet 3 IQ/UenZOr.

July 17, 1928. 1,677,488

0. PEARSON STACKER Filed May 16, 1923 5 Sheets-Sheet 4 Jul 'n, 192s.

' 1,677,488 c. PEARSON STACKER Filed May 16, 1925 I s Sheets-Sheet 5 Patented July 17, 1928.

barren STATES CHARLES rnAnsoN. or CHICAGO, ILnINoIs, assreivon' mo lma vmrbmr*nmvns'rnn. ooI/rPANY, or CHICAGO, ILLINOIS, A conrona'rrolv or NEW easer.

STAGKE'R.

Application filed May 16,

' My invention relates to improvements in quired tooperate a stacker, especially at the beginning of the lift, and to provide improved mechanism. for regulating and operating the extensible head of the stacker so that it will have a wide range of adjustment, give a high lift when required and operate smoothly and without binding or strain.

v A further object is to provide simple means ,for cushioning: the lifting frame both at the end of the lift and at the end of the return or drop. 1

The main objects stated, as well as minor ones that will become apparent as the description proceeds, are attained by providing a structure having improved lever mechanism for hoisting and lowering the stacker head and for controlling the'degree of extension and retraction automatically given it at each operation of the stacker and also novel and simple cushioning mechanism in which a spring which is bodily movable with the lifting frame is made to perform several'functions by being put under tension," through shifting of its points of attachment, at termination of theupward' and downward swings of the lifting frame, whereby it is made to cushion the frame at each end of its movement, assist in raising the frame at the beginning of the lift, when the strain is greatest, and initiatethe re turn movement of the lifting frame. The invention accordingly resides in the organiz ation and details of construction, or equivalents thereof, hereinafter described and claimed.

In the drawings Fig. l is a plan view of a stacker embodying my invention; 7 V v a Fig. 2 is a side view with the stacker in lowered position;

Fig. 3 is a similar view showing the stacker, raised; a a

Y Figfl is an enlarged detail view showing the links and spring connecting the main and secondary lifting arms;

Fig. 5 isan enlarged detail view ofthe .1923. Serial mfeaazas.

coupling between ,the liftcontrolling slide and link; Fig. 6 Fig. 2 showing the pivot connection ofa lifting rod; H V i Y I '7 is aside view 011 an enlarged scale .ofthe partswcomprising the elevating connections, with the relative positions of. the parts at intermediatestage ofelevation indicatedin dotted lines; I f 3 p Fig. 8 is an enlarged detail view on line 88 of Fig. 7 v r Fig. 9 is a similar view on line 9 -9. of Fig.7; Y Fig. 10 is aside view as in Fig. ,3 but with the extension set for extreme height 5 and V Fig. 11 is an enlargeddetail View. ofthe central portion of Fig. 10 omitting the outer ar of the connecting linkto show the spring 'COHIIQChlOIl.

is a detail view line 6-6.io-f

My improved stacker comprises- .a base composed of parallel side sills and21 connected at front, and rear. at an intermediate point by crosspieces22l The. front .of this base frame is preferably supported on an axle and wheels 23 carried on journal brackets. .23 and thefaxle. be cranked as shownand made vertically adjusta ble in any suitable manner. ,At the rear, the baseframe has a rigid vertical portion which may :be composed ofthree vertical posts 24, one at each corner of the frame and .one midway between, which are secured to the side sllls and rearcrosspiece.

.These posts are connected at the .top by transverse member 25 and are suitably braced as by the diagonal side -members; 126 andfdiverg'ing rods 27; At points towards the rear of the sills 20 and 21, there are secured short vertical standards 28 to which are pivoted the main lifting arms .29 of the I the, front ends of the main arms and by guide "brackets 33 (F ig; 9) secured o'n'the rear ends of the extension arms 31 andextending below the main arms 29 where they carry rollers which travel on the lower edges of arms 29. These extension arms carry the stacker head which may be of any usual or preferred construction. Secondarylifting or radiusarms 36 are pivoted "on the upper ends of the corner posts 24 and extend toward the main lifting arms, their point of connection to the base frame being forward of the lifting arms, as shown in the drawings, and links 37 each composed of a pair of spaced parallel bars pivoted on opposite sides'of the ends of the arms 36 and to the main arms 29 toward their outer ends, as bestseen; in Figs. 1, 4 and 8, serve to pivotally connect the main and secondary lifting arms. As the radius arms 36 are pivoted attlie top of-posts 24 the connecting point of the links 37 to arms 36' is more distant from the base'frame than is'the connecting point between the links and the main arms 29, the links 37 swinging through an arc of substantially 180 degrees as the lifting frame operates, and by reason of the arrangement of pivotal points stated, links 37 act as stops for the lifting frame when the limit of their upward swing is reached, as in Fig. 10. The movement of links 37 is also made use of in connection with resilient means hereinafter described,

for modifying the movement'of the lifting frame. To reduce friction, the pivots for links :37 preferablv include bearing sleeves having spacing collars 37' (Fig. 8). Lift- .ing arms 29 and 36 together with the connecting links 37 afford a construction which becomes rigid when the secondary arms 36 reach a substantially vertical position, that is, further swing of the liftingframe toward the stack is automatically stopped by the links 37 when the parts reach the positions seen in Figs. 3 and 10. Need of a buffer frame is therefore eliminated. The

secondary arms 36 control the lift of the extension arms 3.1 and are connected to the extension arms by an adjustable coupling comprising slidable sleeves 38, movable on arms 36, which are connected by flexible linkage, such as rods 39 and chain links 40 (Fig. 5), to upwardly projecting arms of the brackets 33 on arms 31. The arms 36 are provided with means for controlling the extent of movement of sleeves 3 8 consisting. for instance, of a series of spaced aperture's 41 and stop pins 42 which are adapted for insertion in any of the apertures to limit movement of sleeves 38 on the secondary lifting arms 36.. In connection with the parallel bars'composing the links 37, which connect the main and secondary n lifting arm's, there is provided a spring tension device composed'of contractile springs 43 positioned between the bars .of links 37 and attached thereto at their upper ends by a pivoted staple 43 while their opposite ends are attached to short rods 44 pivoted on bracket members 45 secured to the mainlifting arms 29 and extending above the extension arms 31, as shown in detail in Figs. 7 and 8, the pivot point of rods 44 being just above that of links 37. As means for applying power to raise and lower the lifting arms, there is provided a vertically swing ing jib composed of upwardly converging beams 46 which are pivoted on the side sills at their lower ends and rigidly connected near their upper ends as by cross piece 47. The members 46 of the jib have their outer ends connected to the. ends of'thc main lifting arms 29 by means of lifting rods 48 which are pivoted to the endsof the jib members and to the lifting arms, thepivotal connection to the lifting arms: being preferably formed by 'journaling the outwardly bent ends of the lifting rods in openings through arms 29 and the members of' yoke 32, as clearly shown in Fig. 6. Between the ends of the jib members 46, there is journaled a sheave or pulley '49 on each side of which are pivoted the arms of a U-shaped clevis member Twin sheaves 51 are journaled centrally of the transverse bar 25 of the rear end of the base frame and another sheave 52 is mounted immediately below these on the base of the frame. An operating cable 53 is attached to the clevis on the end of the jib and extends over one of the sheaves 51, aroundsheave 49 on the end of the iib, then over. the second sheave-51, and finally under sheave 52 from which it extends to the source of power.

f The operation. of the stacker is effected through the cable 53in the usual way, the

lifting elements in my novel organization functioning inthe following manner :when the device is in lowered position, as in Fig, 2, the relation of parts is such that springs 43 are under tension and are positioned so that they exert a lifting actionon arms 29. If cable 53 is now pulled, the. jib will begin its swing and lifting rods 48 will pull up ward on lifting arms 29 and the assistance of springs 43 will cause lifting movement to start without strain and with application of less power to the cable than heretofore required in old constructions. As lifting progresses and the parts reach the intermediate positions shown in dotted lines on Fig. 7, the springs 43 become slack and as the main and secondary arms'ris-e, the links 37 con necting them swing in such a way that the up per ends of springs 43, which are connected thereto, are shifted from one side of their points of connection to arms 29 to the other side thereof and as the end of the raising movement is reached, the springs are again placed under tension, shown in F 3,

and the end of the upward swing is cushioned in a manner to give the load carried by the head35 a pitching impulse,thetension of springs 43 then causing thc lifting arms, which have passed dead center, to re .38 were free to slideon said arms.

arms as the lift progressed andthere was.

no extension of arms 31 and no additional lift given the stacker head. If it is desired to increase the lift, the pins 42 are placed in the last opening 41, for instance, so that sleeves 38 can have no sliding movement,

consequently they will transmit a pull through the flexiblecouplings 39 and 40, as the lift progresses, to the inner ends of the extension arms 31 and these will accordingly slide outwardly on the main lifting arms 29 and finally assume the position illustrated in Fig. 10. It will be evident that the degree of extension given the arms 31 will be governed by the position of stop pins 42 on arms 36, and that the height of lift can be gradually stepped up to follow a rising stack.

It will be clear from the above description that I have devised an improved construction that is simple, strong and easily operated and in which the height of lift can be quickly and easily adjusted within a considerable range, and that the novel features of construction above described are capableof considerable variation within the scope of the following claims.

I claim as my invention:

1, The combination of a base frame, a lifting frame pivoted thereon to swing vertically through a predetermined are, means for swinging the lifting frame, a spring carried on said lifting frame and bodily movable therewith, and means actuated by movement of said frame for putting the spring under tension at both ends of the arc of movement of the frame.

2. The combination of a base frame, a lifting frame pivoted thereon to swing ver tically through a predetermined arc, means for swinging the lifting frame, a spring with one end connected to said frame and its other end connected to a point of support shiftable with respect to said lifting frame, and means actuated by movement 'of said frame for shifting said support and re versing the action of the spring at each end of the arc of movement of the frame.

3. The combination of a base frame, a lifting frame pivoted thereon to swing vertically through a predetermined are, means for swinging the lifting frame, a contractlie spring with one end connected to said lifting frame and its other end connected to'a link pivotally mounted on' the lifting frame at a point eccentric to the point of connection of the spring thereto, and means act uatedby movement-of; said frame for swinging the link on its'pivot'and shifting the spring from one side of its connection to the frame to the other. i

4. The combination of a base frame,

lifting frame pivoted thereon to swing vertically through a predetermined are, means for swinging the lifting frame, a contractile spring with one end connected to said lifting frame and its other end connected to a link having one end pivoted to the lifting frame at a point eccentric to the point of connection of the spring thereto, an arm pivoted on the base frame to swing in the same direction as the lifting frame, and a pivotal connection between said arm and the other end of said link.

5. The combination of a base frame, a lifting frame pivoted thereon comprising a main lifting arm and an extension arm slidably mounted thereon, means for swinging the lifting frame, a secondary lifting arm pivoted on the base frame to swing in the same direction as the lifting frame,a link pivotally connecting said secondary arm with the main lifting arm, and a flexible coupling between said secondary arm and the extensionarm.

6, The combination of a base frame a lifting frame pivoted thereon comprising a main lifting arm and an extension arm slidably mounted thereon, means for swinging the lifting frame, a secondary lifting arm pivotally connecting said secondary arm with the main llfting arm, a'fiexible coupling between said secondary arm and the pivoted on the base frame to swing in the I same direction asthe lifting frame, a link the lifting frame, a secondary lifting arm,

pivoted on the base frame to swing in the same direction as the lifting frame, a link pivotally connecting said secondary arm with the main lifting arm, a flexible coupling between said secondary arm and the extension arm including a slidable member mounted on said secondary arm, and means for regulating the extent of movement of the slidable member on said arm.

8. The combination of a base frame, a

lifting framepivoted thereon to swing vertically, and means for limiting the arc of movement of the lifting frame comprising an arm pivoted on the base frame to swing with the lifting frame and a link pivotally connecting said arm and lifting frame, the

Connection of the link to the lifting frame the end of said radius arm,.whereby said being nearer the base than the connection of link is swung from one side to the other of i the link to the arm. its pivot to the lifting frame at each ao- 9. The combination of a base frame, a tuation thereof and the limit of movement 5 lifting frame pivoted thereon to swing verin one direction between said link and its 16 tically, a radius arm pivoted on the base connections is reached Whenthe lifting frame to swing with the lifting frame and frame is at the end of its upward swing. spaced therefrom, a link pivotedto the end In testimony whereof I affix my signature,

of said radius arm and pivoted to the lifting w 10 frame at a point nearer the base frame than CHARLES PEARSON. 

